This invention relates generally to a method for transesterification of triglycerides with methanol to produce fatty acid methyl esters.
High fuel prices and environmental concerns are driving development of alternative fuels, especially those derived from renewable resources. One such fuel, commonly known as “biodiesel” fuel, contains methyl esters of fatty acids, and is burned in diesel engines. Biodiesel fuel is produced from transesterification of triglycerides, such as vegetable oils, with methanol. For example, Abreu, F. R. et al.; in Journal of Molecular Catalysis A: Chemical (2005), 227(1-2), 263-267; demonstrated that the tin compound Sn(3-hydroxy-2-methyl-4-pyrone)2(H2O)2 exhibited high catalytic activity for the methanolysis of vegetable oil. However, when this compound was immobilized on an ion exchange resin to facilitate re-use of the catalyst, it lost all activity.
The problem addressed by this invention is to find an improved method for transesterification of triglycerides with methanol, especially those containing significant levels of free fatty acids (1-99%).